Propeller



,056 April 2.6., 1927' M. D. THOMPSON PELLER Filed March 14, 1925 MQWIQM i My invention relates to propeller-Wheels .which'the blades, when not revolvin T in case the sails are used as Patented Apr. 26, 192 7.

Lasts MILTON D. THQKPSON, OI FAIBHAVEN, MASSACHUSETTS Application filed ital-ch 14, 1925. Serial No. 15,818.

. and more especially to that type of wheel in the shaft, may feather or turn on their axes a certain amount.

' This type of wheel is quite largely used.

on sail craft equipped with auxiliary motor driven propulsion and is extremely valuable the propelling agent..."

In feathering the blades, their sharp ens dent with that of the direction of travel a'large amount of resistance to the movement of the latter when under sail power.

In some. types of feathering propeller wheels a tube or sleeve is employed to actuoperated by a lever or screw arrangement. This style of construction necessitates-a I certain amount of complication in themeohate the blades in bringing them into feathering position. This'sleeveencases the shaft, extends from the propellerinboar'd and-is anism and its operation is often attended with more or less difiiculties, requires coni stant attentionand frequent repairs, which,

' are quite apt to be expensive.

- no outside mechanical devices to bring it to make a'much longer life and fewer replacements. It will on account of the inacessibility of the parts,

One of the princi 1 objects of my'in vention is to provi 'e a feathering blade which is automatic in its action,-requiring "into the feathering position,-depending wholly on the force of the water against the rearward portion of the blade to produce the result. r

' Another object is to eliminate many of the I parts required in the sleeve or positively In doing this I am enabled operated types.

stronger propeller, insuring also relieve the engineer of the craft of all care or thoughtrelative to the featheringof the blades, as immediately upon stopping hisimotor the blades automatically adjust themselves to the fore'and aft, or feathering.

posit-ion. Other objects of my invention will be apparent from a consideration of the detailed description hereinafter. found in my specification when taken in connection with theaccompanying drawing wherein a preferable embodiment of my invention is shown and with ring

tering edgescut the water in a plane cinci- .war part of the cas ng;

of the boat or ship and therefore do not'ofl'er hub (3') of the blade is ap intle 5. 1

' posite each other.

Fig. 2 is a view, in perspective, of one of 60 the blades;

Fig. 3 is 'a'view, sleeve; x

, Flg. 4 is a view, perspctive, of the cam.

in perspective, ofthe cam Fi 5 is a view, in perspective, bf the f.

Fig. 6 is a view in perspective of rearward of aft part-of the casing;

F g. 7 1s a transverse sectional view, taken on l1ne-77, Fig. 8;

Fi s is a longitudinalsectional elevation," 1

showing some parts in full, and taken on a central line through the casing, as on line 88 Fig. 7;

Fig. 9' 1s a view representing the blade in ahead and astern positions in full lines, and

in feathering position in dot and dash lines;

and Figs. 10 and'll are diagrammatical illustratlons showing tlie efi'ect of pitch angles oftheblades.

9 Referring to the'drawings, 1 is the pro-' peller shaft, 2 is a blade; 3 is the hub of the 2 blade and 4- is a scored recess in the'hub.

Eccentrically. positioned on'the end of this Fixedon the. shaft 1 is the cam sleeve 6. I

having cut therein a groove or path 7; This cam path starts at the after end of-the sleeve (6) and is parallel to the axis of the shaft for a spaced distance when it bifurcatesinto' two spirally out grooves or fin-ways,one right land and the other lefthand. There are two sets of these paths on the periphery of the sleeve (6), placed diametrlcally op- The diameter of the forward end of the'sleeve, at 6'-' is somewhat enlarged, and theopposite end at 6" is re-- duced, relative to the diameter of the central 3 portion thereof. Loosely mounted over .the central portion of the cam sleeve 6 is a cam ring 8, which is adapted to not only'slide longitudinally of the sleeve but to oscillate thereon a'predeter mined amount. This combined movement of the cam-ring (8) is produced by the an. gagement of the cam path with the pins 9 ctive, of my' han the f ashell of substantially spherical shape.

y and occurs whenever the shaft starts to ro- Ears .12 projecting outwardl from the part 12 enter the part 11 and y means of the screws 13' secure one partto the other.

6n the periphery of the shell, and cen-.

trally of the joint line, are apertures 14: in which operate and are sccuredthe hubs of the blades,the hicitness of the shell at these openings being such as to fill the recess iin the hub 3 of theblade-and allows the latter to oscillate therein at certain times,

'. but prevents its withdrawal from the casing.

Abutting the reduced end the, sleeve 5, et 'ii", is a collar 15 made somewhat larger than the portion 6?. The nut 16 on the rearward end of the shaft 1 secures this collar (15) as well as the sleeve 6 rigidly on the shaft. A circumferential recess is thus formed on the aft end of the sleeve 6 and this operates the internal collared portion 17 which controls an of the threaded thrust bushing i8,-the lat ter being screwed into the portion lEZ oL the casing and providing means for securing the conical cap 19 to the casing. it will be seen that this collared ortion 17 is the element (i locates the position, iongitudinally'on the shaft, of the casing or shell part of the propeller upon the sleeve 6.

Another functlon' of this collar, and the threaded bushing, of which this collar is a part, with its capacity for longitud nal adjustment in and out of the casing, wiil here 'inafter'be disclosed.

As I have reviously stated in my preamble, the bla es of my propeller are capable of feathering automatically. By reference to'Figs. 8 and 9, and the following explana tion, it will be apparent how this result is accomplished.

In the first place let us assume that the blades are in the feathering position and the shaft 1 is to rotate in a right-handed direction,-or as indicated by the arrow in full lines in Fig. 8,and that we are employing a right-handed blade relative to its pitch angle. Then-as the cam sleeve 6 is fixed on the shaft 1, the rotation of the latter combined with the resistance of the water against the working of the blade will result in oscillating it on its axis and bringing the pins 9 to the terminus of the cam path 7, or at the point marked 6 in Figs. 3 and 8, with the blade positioned, in relation to its pitch angle, as seen at w'-r, Fig. 9. The In order to key the cam ring 8 to thecasengagement of the pintles 5 by the sides of the depressions 10 is the immediate cause of the changing of the blades from feathering to ahead position, the action being comparable to that of a connecting rod on a 'crank-pin,the latter representing the pintle 5 and the former the sides of the depression 10. 1

If the rotation of the shaft 1 is continued 1n the right-handed direction the pins 9 will remain in the ends of the path 7 at b, and the craft will be propelled in a forward direction,

Immediately on stopping the motor, however, which will cause the shaft 1 and the cam sleeve 6 to remain stationary, the resistance of the water against the back side of the blades, as the craft still has headway, will cause themto'oscillate on their axes, and the pintles 5 to swing the cam ring 8 backwardly on the sleeve 6 bringing the pins 9 again into the junction of the two spiral grooves or paths 7, as at a. The blade now assumes the position it was in at the start, or feathering, as seen at yy, Fig. 9, and it will remain thus until some further rotation of the shaft 1 takes place.

Before, passing to the next step in the operation of the propeller it might be well to state that the blades of my propeller wheel are of the so-called unbalanced type,-in other words,fhere is more surface contact with the-water on the aft or rearward side of their axes than on the forward side, so that when the shaft is idling and the craft -under way the resistance of rthe water against the blades wili straighten them out,

much as the tail of a weather vane will. bring the whole vane into a direction corresponding to that from which the wind is biowing.

Thus far I have described the actuation and positionsof the blades in feathering and go ahead positions, and have made clear,

also, that whenever the motor stops the blades will come into feathering position.

Starting again from this latter position,

and driving the shaft 1 in the opposite or V astern direction as indicated by the arrow in dotted lines, Fig. 8, the first action is of the cam sleeve 6 oscillating in the casing sufiicientl to bring the ins 9 into the terminals o the right-hand 8 forwardly on the sleeve 6 and swing the blades into the same positions, relative to their pitch angles, as obtained when the shaft was rotating to cause a forward movespiral portions, of i the path 7. This will move the cam ring eating freely in the casing and along the" surface of the sleeve 6.

Reverting to a consideration of the function of the threaded-bushing 18 itwill be seen by viewing the different figures in the drawing that the pins 9 and the pintles are at all times in the same plane, transversely of the shaft '1.

' It will also be apparent that the terini nal points a and b in the path 7 mark the extreme movements, in one longitudinal direction, of the pins 9 at any and all pitch angles of the blades. This establishes a distance, variable in different pitch angles of the blades, between two planes running transversely of the shaft 1,-one plane cutting the axis of the hub of the blade 2 and the other axis of the pintle 5. Now the movement of the cam ring 8 alon the sleeve 6 acts to move the pintles 5, hel in the'depress'ions 10 of the ring, in an are,the axes of the blade hubs 3 oscillating in the apertures 14 of the casing, being the center of turning point.

Therefore when the threaded bushing 18 is screwed into or out of the casing member 12, this distance, just mentioned, between the two lanes becomes changed and has the effect 0 lengthening or shortening,respee-' tively, the action of the pintles 5, resulting in producing afiner or coarser pitch angle to the blades 2. 1

At any pitch angle of the propeller, and with the craft being moved thereby either forwardly or backwardly, the pins 9 will come to a seat in the terminal points of the -path'7, at either 6 or a, respectively, and

to allow proper clearance for these pins '(9) when the blade is feathering and a fine pitch angle is employed the junction of the two branches of the path, at c, is made somescrewed further into the casing 12, resulting;

in a lar or are of action m for the pintle 5 and allowing the blade to come to a finer pitch angle .n, In Fig. 11 the reverse takes place by screwing the bushing out offthe casing a certain amount. .z

I have illustrated my propeller as of the three-bladed type, but it is very a parent that a greater or less number, as our or two might be employed with equal facility.

And while I preferably choose to construct the parts as illustrated and described,

I elect, and shall consider myself at -liberty to depart from the exact mechanical details as herein portrayed, provided, however that any such changes shall not depart from the spirit and intentof the invention and fall within the scope of the appended claims.

Iclaim:-- r

1 In a feathering and reversing propeller, the combination, of a shaft, a hub fixed on said shaft, a pin-way on said hub, starting at the after end thereof and diverging into two pin-ways, one spiralling to the right hand and the other to the left hand, a camrin mounted on said hub and adapted to both oscillate and reciprocate thereon, .pins on the inner periphery of said cam-ring, adapted to be engaged by said pin-ways, a transversely jointed casing, the forward art bearing on an enlarged portion ofsaid ub, bearings equally spaced about the periphery of said casing, propeller blades oscillatively operable in the said bearings and with hubs having circumferential grooves, the collars thus formed being,the one on the inner and the other on the-outer side of said casing, pins eccentrlcally placed and inwardly disposed on the ends of said propeller hubs,

slots on the outer peripheryof said camring, their' sides adapted to engage said pins in sa1d(propeller hu 5 and means for securing sai casing against longitudinal movement on said shaft.

ill!

2; In a feathering and reversing (propeller,

inn

ment thereon, pin-ways on the periphery of said cam-rin adapted to engage; the pins in said prope ler blade hubs, means to actuate said cam-ring and means to secure said casing in various positions, lon itudinally,

on said shaft hub, whereby the istance between the transverse lanes cutting the centers of the propeller lade hubs, ma be varied for the purpose of changing to pitch angles of said propeller blades.

3. Ina propeller, the combination of a shaft, a shaft hub fixed to said shaft, 8. diverging in-way on said hub with its apex rearward y disposed, a cam-ring mounted over said hub, pins on the inner periphery of said cam-ring adapted to operate in and to be engaged by the said diverging pin-way, a

two-part casing oscillatively mounted on 7 said shaft hub, means for keying said cam ring and said'ca'sing together whereby they may oscillate in unison but be independent in their longitudinal movements, bearings on the periphery of said casing, propeller blades mounted in said bearings, means to oscillate said propeller blades in said Dear-- ings, means to locate said casing in various and predetermined positions axially of and along the said shaft hub, and a conical cap adapted to serve as covering means for the end of said shaft and a check for said casing.

A v 4. A feathering and reversing propeller comprising, in combination, a rotatable shaft; a casing carried by said shaft; pro-- peller blades oscillatively mounted on said casing for movement between propelling position and feathering position; a cam-r1ng R mounted on said Shaft within the casing and movable longitudinally along said shaft; operative connection between said cam-ring and said blades whereby the blades are oscillated upon longitudinal movement of said 2" cam-ring; and operative connection between cam-ring is caused to move longitudinally upon rotation of said shaft to effect oscillationof tbeblades into propelling position.

5. A feathering and reversing propeller, comprising, in' combination, a rotatable shaft; a casing carried thereby and adjustable therealong; propeller blades oscillative lv mounted on said casing for movement between propelling position and feathering position; means operatively connecting said shaft and said blades whereby upon rotation of said shaft the said blades are oscillated into propelling position; and means for adjust ing the position of said casing along said 35. shaft whereby the operation of said connect- 'ing means is varied to effect different angular settings of the blades with respect to their axis of oscillation.

MILTON D. THOMPSON. 

